• Vaccine Name: G. duodenalis DNA vaccine encoding CWP2
• Target Pathogen: Giardia duodenalis
• Target Disease: Giardiasis (Beaver fever)
• Vaccine Ontology ID: VO_0011550
• Type: DNA vaccine
• Status: Research
• Antigen: G. duodenalis cyst wall protein-2 (CWP2)
• CWP2 gene engineering:
  • Type: DNA vaccine construction
  • Description: The cwp2 open reading frame was amplified by PCR and sub-cloned between the EcoRI and NotI restriction sites in the multiple cloning site of pCDNA3. Both the empty and recombinant pCDNA3 plasmids were purified from transformed Escherichia coli DH5α using the Qiafilter plasmid purification kit from Qiagen (Ont., Canada) according to the manufacturer's instructions. The plasmids were transformed into the SL1655 restriction modified strain of S. typhimurium (kindly provided by Dr. Ken Sanderson; Salmonella genetic stock center, Calgary, Canada) to stabilize the plasmids in STM1, and then purified and re-introduced into the STM1 strain of S. typhimurium (kindly provided by Dr. Peter Smooker; RMIT University, Melbourne, Australia). All bacterial cultures were maintained in Lauria Bertani (LB) culture medium supplemented with ampicillin (150 μg per mL) (Abdul-Wahid and Faubert, 2007).
  • Detailed Gene Information: Click Here.
• DNA vaccine plasmid:
  • DNA vaccine plasmid name:
  • DNA vaccine plasmid VO ID: VO_0000132
• Immunization Route: Oral

Mouse Response

• Host Strain: BALB/c
• Vaccination Protocol: For oral DNA immunization, mid-log phase Salmonellae were collected by centrifugation and re-suspended in ice cold PBS. Mice were orally immunized with 300 μL containing 10^9 CFUs by gavage using a blunt-ended probe. The animals were immunized every 2 weeks for a total of three immunizations. This dose and regimen were used as they were found to stimulate the highest level of CWP2-specific immune response without causing any toxic side effects to the mice (Abdul-Wahid and Faubert, 2007).
• Challenge Protocol: DNA immunized and control mice (n = 12 mice per group) were challenged with 10^5 G. muris cysts a week following the last immunization (Abdul-Wahid and Faubert, 2007).
• Efficacy: The gene encoding the full length cyst wall protein-2 (CWP2) from Giardia lamblia was subcloned into the pCDNA3 mammalian expression vector and stably introduced into S. typhimurium STM1. Challenge infection with live Giardia muris cysts revealed that mice receiving the CWP2-encoding DNA vaccine were able to reduce cyst shedding by approximately 60% compared to control mice (Abdul-Wahid and Faubert, 2007).